Borealis Ag

Eric-Jan Prinsen

Klaus Nyfors

Vasileios Kanellopoulos

Gunter Weickert

Erno Elovainio

Pablo Ivan Aguayo Arellano

Günter Weickert

Mohammad Al-Haj Ali

Apostolos Krallis

Apostólos Krallis

The present invention relates to a method for improving the cooling capacity of a gas solids olefin polymerization reactor by splitting the fluidization gas and returning part of the fluidization gas to the reactor into the bottom zone of the reactor and another part of the fluidization gas directly into the dense phase formed by particles of a polymer of the at least one olefin suspended in an upwards flowing stream of the fluidization gas in the middle zone of the reactor.

Method for improving the cooling capacity of a gas solids olefin polymerization reactor

The present invention relates to a process for polymerizing olefin monomer(s) in a gas solids olefin polymerization reactor wherein the fluidization gas is split and returned to the reactor into the bottom zone of the reactor and directly into the dense phase formed by particles of a polymer of the olefin monomer(s) suspended in an upwards flowing stream of the fluidization gas in the middle zone of the reactor.

Method of splitting the return fluidization gas in a gas solids olefin polymerization reactor

The present invention relates to a process for removing polymer material from a gas-solids olefin polymerization reactor wherein the gas-solids olefin polymerization reactor is connected to the top part of an outlet vessel via a feed pipe wherein the powder surface of discharged polymer material and the barrier gas injection point are situated in the outlet vessel as such to fulfill the following criteria: R'=X/Y&#x2264;2.0; and R&#x2033;=X/D&#x2265;1.0; wherein X=Distance between the powder surface and the barrier gas injection point; Y=Distance between the barrier gas injection point and the vessel outlet; and D=Equivalent outlet vessel diameter, an apparatus for continuously removing polymer material comprising a gas-solids olefin polymerization reactor, an outlet vessel and a feed pipe connecting the gas-solids olefin polymerization reactor with the top part of the outlet vessel and the use of said apparatus for polymerizing alpha-olefin homo- or copolymers having alpha-olefin monomer units of from 2 to 12 carbon atoms and for increasing the barrier gas efficiency of the gas-solids olefin reactor to at least 75%.

Process and apparatus for removing polymer material from a gas-solids olefin polymerization reactor

The present invention relates to a process and apparatus for withdrawing polymer agglomerates from a fluidised bed polymerisation reactor, the polymerisation reactor comprising a bottom zone having a generally conical shape and no fluidisation grid. The agglomerates are withdrawn by using an agglomerate trap below the bottom zone. A value of a process variable indicative of the content of agglomerates in the agglomerate trap is measured and the opening time of the valves transferring polymer to and from the agglomerate trap is adjusted based on the measured value.

Method for withdrawing agglomerates from a fluidized bed polymerization reactor

The present invention deals with a process of polymerising at least one olefin in a fluidised bed in a fluidised bed polymerisation reactor comprising a top zone, a middle zone in direct contact and below, a bottom zone in direct contact with and below the middle zone and wherein the reactor does not comprise a fluidisation grid. The process comprises passing a stream comprising the fluidisation gas and polymer particles into a separation step and withdrawing a stream comprising the polymer particles from the separation step and returning it to the polymerisation reactor. The process comprises adding a support gas stream to the stream comprising the polymer particles downstream of the separation step.

Method for returning polymer to a fluidised bed reactor

The present invention deals with an olefin polymerisation process. At least one olefin is polymerised in gas phase in a fluidised bed in the presence of an olefin polymerisation catalyst in a polymerisation reactor having a vertical body; a generally conical downwards tapering bottom zone; a generally cylindrical middle zone above and connected to said bottom zone; and a generally conical upwards tapering top zone above and connected to said middle zone. Fluidisation gas is introduced to the bottom zone of the reactor from where it passes upwards through the reactor, and withdrawn from the top zone of the reactor. The gas is then compressed, cooled and returned into the bottom zone of the reactor. A fluidised bed is thus formed within the reactor where the growing polymer particles are suspended in the upwards rising gas stream wherein the superficial velocity of the fluidisation gas is less than the transport velocity of the particles. There is no fluidisation grid in the reactor. The fluidisation gas is passed from an inlet chamber into the bottom zone and the gas flows from the upper part of the inlet chamber to the lower part thereof and the gas flows from the lower part of the inlet chamber to the bottom zone.

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Aadorp, Netherlands

Eric-Jan Prinsen